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Why is the shovel operator (
...g a new one. The reason for this is that in ruby a += b is syntactic shorthand for a = a + b (the same goes for the other <op>= operators) which is an assignment. On the other hand << is an alias of concat() which alters the receiver in-place.
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Accessing nested JavaScript objects and arays by string path
...your property name contains '[]' in itself. Regex will replace it with '.' and it doesn't work as expected
– Capaj
Jul 30 '15 at 21:57
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Checking for NULL pointer in C/C++ [closed]
...ol NULL. They do not expose the opportunity for the accidental assignment. And they are clear and succinct.
Edit: As SoapBox points out in a comment, they are compatible with C++ classes such as auto_ptr that are objects that act as pointers and which provide a conversion to bool to enable exactly...
Two-dimensional array in Swift
I get so confused about 2D arrays in Swift. Let me describe step by step. And would you please correct me if I am wrong.
8 ...
Printf width specifier to maintain precision of floating-point value
...eventh = 1.0/7.0 results in the value below. Also shown are the preceding and following representable double floating point numbers.
OneSeventh before = 0.1428571428571428 214571170656199683435261249542236328125
OneSeventh = 0.1428571428571428 49212692681248881854116916656494140625
OneSeven...
Android phone orientation overview including compass
I've been trying to get my head around the Android orientation sensors for a while.
I thought I understood it. Then I realised I didn't. Now I think (hope) I have a better feeling for it again but I am still not 100%. I will try and explain my patchy understanding of it and hopefully people will be ...
Performance difference for control structures 'for' and 'foreach' in C#
...corlib]System.IDisposable::Dispose()
IL_002f: endfinally
} // end handler
IL_0030: ret
} // end of method Test::IterateOverList
The compiler treats arrays differently, converting a foreach loop basically to a for loop, but not List<T>. Here's the equivalent code for an array:
sta...
Reading output of a command into an array in Bash
I need to read the output of a command in my script into an array. The command is, for example:
3 Answers
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How can I pad a value with leading zeros?
...o readers!
As commenters have pointed out, this solution is "clever", and as
clever solutions often are, it's memory intensive and relatively
slow. If performance is a concern for you, don't use this solution!
Potentially outdated: ECMAScript 2017 includes String.prototype.padStart and...
Calculate the center point of multiple latitude/longitude coordinate pairs
Given a set of latitude and longitude points, how can I calculate the latitude and longitude of the center point of that set (aka a point that would center a view on all points)?
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